<!--$Id: mgr_meth.so,v 1.10 2008/04/23 13:35:47 sue Exp $-->
<!--Copyright (c) 1997,2008 Oracle.  All rights reserved.-->
<!--See the file LICENSE for redistribution information.-->
<html>
<head>
<title>Berkeley DB Reference Guide: Replication Manager methods</title>
<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit.">
<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++">
</head>
<body bgcolor=white>
<table width="100%"><tr valign=top>
<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Berkeley DB Replication</dl></b></td>
<td align=right><a href="../rep/app.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../rep/base_meth.html"><img src="../../images/next.gif" alt="Next"></a>
</td></tr></table>
<p align=center><b>Replication Manager methods</b></p>
<p>Applications which use the Replication Manager support generally call
the following Berkeley DB methods.  The general pattern is to call various
methods to configure Replication Manager, and then start it by calling
<a href="../../api_c/repmgr_start.html">DB_ENV-&gt;repmgr_start</a>.  Once this initialization is complete, the
application rarely needs to call any of these methods.  (A prime
example of an exception to this rule would be the <a href="../../api_c/rep_sync.html">DB_ENV-&gt;rep_sync</a> method,
if the application is doing <a href="../../ref/rep/mastersync.html">delayed synchronization</a>.)</p>
<br>
<b><a href="../../api_c/repmgr_local_site.html">DB_ENV-&gt;repmgr_set_local_site</a></b><ul compact><li>The <a href="../../api_c/repmgr_local_site.html">DB_ENV-&gt;repmgr_set_local_site</a> method configures the TCP/IP address of
the local site, by specifying the port number on which it is to listen
for incoming connection requests.  This method must be called exactly
once before calling <a href="../../api_c/repmgr_start.html">DB_ENV-&gt;repmgr_start</a>.</ul>
<b><a href="../../api_c/repmgr_remote_site.html">DB_ENV-&gt;repmgr_add_remote_site</a></b><ul compact><li>The <a href="../../api_c/repmgr_remote_site.html">DB_ENV-&gt;repmgr_add_remote_site</a> method adds a remote site to the list of
sites initially known by the local site.  The remote site is specified
in terms of a TCP/IP network address: host name and port number.  This
method may be called as many times as necessary to configure all known
remote sites.  Note that it is usually not necessary for each site in
the replication group initially to know about all other sites in the
group.  Sites can discover each other dynamically, as described in
<a href="../../ref/rep/newsite.html">Connecting to a new site</a>.</ul>
<b><a href="../../api_c/repmgr_ack_policy.html">DB_ENV-&gt;repmgr_set_ack_policy</a></b><ul compact><li>The <a href="../../api_c/repmgr_ack_policy.html">DB_ENV-&gt;repmgr_set_ack_policy</a> method configures the acknowledgement
policy to be used in the replication group, in other words, the
behavior of the master with respect to acknowledgements for
"permanent" messages, which implements the application's requirements
for <a href="../../ref/rep/trans.html">transactional guarantees</a>.  The
current implementation requires all sites in the replication group
configure the same acknowledgement policy.</ul>
<b><a href="../../api_c/rep_nsites.html">DB_ENV-&gt;rep_set_nsites</a></b><ul compact><li>The <a href="../../api_c/rep_nsites.html">DB_ENV-&gt;rep_set_nsites</a> method tells Replication Manager the total number
of sites in the replication group.  This is usually necessary for
proper operation of elections, and for counting message
acknowledgements (depending on the acknowledgement policy).</ul>
<b><a href="../../api_c/rep_priority.html">DB_ENV-&gt;rep_set_priority</a></b><ul compact><li>The <a href="../../api_c/rep_priority.html">DB_ENV-&gt;rep_set_priority</a> method configures the local site's priority for
the purpose of elections.</ul>
<b><a href="../../api_c/rep_timeout.html">DB_ENV-&gt;rep_set_timeout</a></b><ul compact><li>This method optionally configures various timeout values.  Otherwise
default timeout values as specified in <a href="../../api_c/rep_timeout.html">DB_ENV-&gt;rep_set_timeout</a> are
used.  In particular, Replication Manager client sites can be
configured to monitor the health of the TCP/IP connection to the
master site using heartbeat messages.  If the client receives no
messages from the master for a certain amount of time, it considers
the connection to be broken, and calls for an election to choose a new
master.</ul>
<b><a href="../../api_c/env_event_notify.html">DB_ENV-&gt;set_event_notify</a></b><ul compact><li>Once configured and started, Replication Manager does virtually all of
its work in the background, usually without the need for any direct
communication with the application.  However, occasionally events
occur which the application may be interested in knowing about.  The
application can request notification of these events by calling the
<a href="../../api_c/env_event_notify.html">DB_ENV-&gt;set_event_notify</a> method.</ul>
<b><a href="../../api_c/repmgr_start.html">DB_ENV-&gt;repmgr_start</a></b><ul compact><li>The <a href="../../api_c/repmgr_start.html">DB_ENV-&gt;repmgr_start</a> method starts the replication system.  It opens the
listening TCP/IP socket and creates all the background processing
threads that will be needed.</ul>
<br>
<p>In addition to the methods previously described, Replication Manager
applications may also call the following methods, as needed:
<a href="../../api_c/rep_config.html">DB_ENV-&gt;rep_set_config</a>, <a href="../../api_c/rep_limit.html">DB_ENV-&gt;rep_set_limit</a>, <a href="../../api_c/rep_request.html">DB_ENV-&gt;rep_set_request</a>,
<a href="../../api_c/rep_sync.html">DB_ENV-&gt;rep_sync</a>, <a href="../../api_c/rep_stat.html">DB_ENV-&gt;rep_stat</a>.</p>
<table width="100%"><tr><td><br></td><td align=right><a href="../rep/app.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../rep/base_meth.html"><img src="../../images/next.gif" alt="Next"></a>
</td></tr></table>
<p><font size=1>Copyright (c) 1996,2008 Oracle.  All rights reserved.</font>
</body>
</html>
